The Cognitive Science of evolutionary psychology

CGSC 1001Mysteries of the Mind

by Jim [email protected]

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Occurs whenever these three things exist:• Generation of diversity

Mutation, crossover

• Selective reproduction and

Survival and reproduction of the fittest

• Transmitted change

Genetic, taught, imitated

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http://www.youtube.com/watch?v=JBgG_V

SP7f8 (4:10)

Here’s another evolution, this time of

walking: http://io9.com/watch-as-these-

adorable-robots-evolve-the-ability-to-wa-

480989422

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Natural Selection Sexual Selection Artificial Selection (e.g., breeding) http://www.youtube.com/watch?v=EoB0pdhxfZs (9:43) Evolution in Action: The Silver Fox

Experiment If you’re interested in learning more about the

silver fox experiment, listen to this RadioLabepisode, “New Nice”

http://www.radiolab.org/2009/oct/19/new-nice/

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Originally, the “typica”

moth (right) flourished in

England, because it

blended in with the

lichens on trees. During

the industrial revolution,

the trees became

covered with soot,

resulting in the flourishing

of the darker “carbonaria”

(left). When England

cleaned itself up, “typica”

made a comeback.

By Jonathan

Weiner (1995)

Finch beaks

evolve with the

weather!

One of my

favourite books

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Explaining psychological traits as

evolutionary adaptations.

Adaptationism: theorizing about

evolutionary causes for phenotypes.

Evolutionary psychology generates

hypotheses, but these must be tested.

Many people will believe an evolutionary

story without evidence.

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Predetermination• Mostly independent of environment (e.g., eye colour)

Some traits are useless• Male nipples. Nipples form before sex is determined.

They are useful for females but only constitute a minor nutritive cost.

• Vestigial organs, such as the appendix.Exaptation

• Something evolved for one purpose is used for another (e.g., female orgasm in primates, bird feathers, jaw bones exapted to inner ear bones in humans).

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Overridable• E.g., bitter foods and drinks, such as coffee

Baldwin Effect (predisposition)• We evolved to learn something easily E.g., language

Cortical and Neural Recycling• We like the taste of aspartame, which has no nutritive

value

Cultural feedback loops• Less hair leads to fewer pests, making fire and

clothing allows it to happen

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Small jawUpright postureBig headLess developmental changeLess aggressionSexual and natural selection

• More violent people get killed

• 10% of people in hunter gatherer societies are killed through capital punishment

We domesticated ourselves

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Our minds evolved, mostly during the Paleolithic (the Environment of Evolutionary Adaptation, or EEA)

Our minds are a collection of special-purpose mechanisms for dealing with specific kinds of problems. It is “modular,” rather than “general purpose.”

These adaptations might no longer be beneficial.

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Recall the Trolley Problem.

What is the evolutionary explanation for

this?

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Evolution predicts that men will be most

attracted to healthy women who can bear

children, and women should be most

attracted to men who will provide

resources to help raise the offspring.

Men like a low waist-to-hip ratio (.7), and

low ratios produce smarter children and

healthier women.

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Smelly T-Shirt experiment• Women want compatible immune systems• Men prefer shirts of ovulating women

Testosterone makes men look more masculine (too much interferes with the immune system)• Women prefer masculine faces when ovulating• Women prefer more feminine faces when not• Women guess that more masculine faced men will be poorer

parents. Testosterone correlates with divorce, infidelity, and violence.

Women prefer high prestige men for long-term commitments, and dominant men for short-term sexual affairs

3-4% of babies come from extra-pair copulations

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Prediction: we should remember better

things for survival.

In a word memory test, this was found to

be true.

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Hamilton’s selfish gene theory We care about people to the extent that they

overlap with us genetically (among other factors, of course)

Why animals sacrifice their lives for offspring Married people show modest correlations (.2) for

breadth of nose, length of earlobe, wrist measurements, distance between eyes, and lung volume. Length of middle finger correlates a whole .61. Similarity in general predicts marital success.

Anybody put a specific lung volume on their lavalife profile?

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Which cards would you have to turn over to find out if the following rule was

true?:

If a card shows an even number on one face, the other side is red.

1 2 3 4

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Which cards would you have to turn over to find out if the following rule was

true?:

If a person is drinking alcohol, they must be over 19 years old.

Fat, salt, protein and sugar are important

nutrients that were rare in the vast majority

of our evolutionary history.

Now we live in a society that has abundant

fat and sugar.

We didn’t evolve to deal with massive

quantities of it– never had to.

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Watch only up to 6:40

http://youtu.be/nNW_B8EwgH4

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